Thursday, January 14, 2010

Wonderful Woodcocks!

A real highlight of the year so far has been the gathering of outrageously tame American Woodcocks around Cape May Point. It started in late December, after the first snow fell; then, woodcocks were coming out to feed at dusk and after dark along road verges where the snow was beginning to clear away sooner than elsewhere. With the ground having been largely frozen since then, they are probably struggling to find food, so are having to spend more time feeding. This means having to feed during the day as well as at night and brings them into closer association with us Humans.

I started by trying to stalk woodcock in the grounds of the Northwood Center - and found it predictably near-impossible!! American Woodcock have eyes placed right round on the sides of the head, which means that they have 360 degree vision! Don't ever think that you can sneak up on a woodcock because they can see you coming from any direction. This is an amazing adaptation, but works well with their cryptic colouration, allowing them to sit tight and keep an eye on any potential predator. If they need to take flight, a whistling sound from the wings draws attention to the bird; this probably helps during the breeding season as it would draw attention away from a vulnerable nest or young. The whistling sound is created by another adaptation, this time to the wings. The outer three primaries have been reduced to thin blades which allows the air to pass between the feathers when they fly and creates the sound. It's a bit like when children put a piece of grass between their thumbs and blow across it; the air speeds up as it passes through the constricted gap and causes the grass to vibrate rapidly, which is what makes the noise.

Having spent time more or less unsuccessfully stalking wary woodock, the continuation of cold weather has pushed them into areas where they can't help but show themselves. At work this has meant the wonderful sight of woodcocks pottering about on the very steps leading up to the store, and ambling around in the front yard. I've seen up to 10 different birds during lunch time sorties around the local block, even coming across birds strolling across the road in the middle of the day! When walking out in the open, they adopt a peculiar rocking or slow bobbing gait which is out of cinc. with their leg movements. I'm not really sure why they do this; some people suggest that it mirrors windblown movements of vegetation, but this wouldn't work if they're going to do it when they're right out in the middle of the road!

(Spot the woodcock! I took this picture from the front door of the store, to show a typical view of a cryptically-coloured bird doing what it does best. If you can't see it, it's in the leaf litter between the bench and the upright posts.)

(Cryptic plumage and bobbing isn't much good when you're crossing the road!)

So, after all my stalking efforts, I eventually came down to just sitting with the birds and photographing them, at times from as little as eight feet or so away. I'd like to think that the local ones might get used to me and maybe I could offer them a few worms - wouldn't it be great to be hand-feeding your local woodcocks?! Having got so close, I could see two other amazing woodcock adaptations. The first is the use of the bill and the method of feeding. All woodcock species have a tactile tip to the bill, so it basically works in exactly the same way as our finger tips. If they touch something with the tip of the bill, they can tell pretty much what it is; whether it's soft, hard, granular, slimy. Ideal for detecting earthworms and soil borne invertebrates that are living below the surface. So, their feeding strategy is to stick their beak into the soil and just feel for a second or two. So this is what they do; they bury their beak and hold still. If there's something there, they will grab it, if not, they lift out and stick the beak in somewhere else. So they're not poking around and turning over the soil, it's a much slower and more measured action.

(American Woodcock in feeding mode, with tactile bill tip placed well below the soil surface.)

The final adaptation was one I was wholly unaware of and discovered when looking closely at the photos I had taken. This adaptation involves the positioning of the ear opening. Birds have open-barbed feathers covering their ear openings which are structured differently to the other feathers on the head. Thus, it is easy to see - on most birds - that the ear opening is situated behind and slightly below the line of the eye. Pretty much as ours are. However, with woodcock, it turns out that the ear opening is actually immediately beneath the front edge of the eye, in the middle of where we would expect the cheek to be! This is remarkable and I'm not sure why it should be that way, unless the ears are angled forwards to listen for invertebrate movement in the soil or leaf litter.

(Note the open-barbed feathers covering the ear opening, in the pale area between the two dark stripes, immediately below the front (left in the picture) edge of the eye.)

The forecast is for slightly warmer weather over the next few days, so I'm expecting my new-found friends to disappear for a while. However, I'll be happy in the knowledge that this actually means that living conditions have improved for them, at least for a while.

(Nicely silhouetted on the front steps as the sun sinks low in the late afternoon.)

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